tyres,which way round?.

Mother wrote:

> On Wed, 20 Jul 2005 17:13:55 +0000 (UTC), "TonyB"
> <[email protected]> wrote:
>
>>This technique successfully cured an out of true wobble on a car I had which
>>had been kerbed. Normal balancing didn't do the job.
>
>
> I'm somewhat concerned to believe that balancing a wheel 'on the
> vehicle' should be seen as a viable option to compensate for damaged
> steering or suspension.
>
Balancing on the vehicle would not compensate for any damage to the
steering or suspension. As such components do not rotate the question of
balancing is irrelevant. However the effects of a less than perfectly
unbalanced wheel may be more obvious if there is steering/suspension
damage or wear.

The advantage of balancing on the vehicle is that it is a way of
enabling any imbalance of rotating parts other than the wheel/tyre to be
treated without dismantling and balancing each individually. That
imbalance may not be the result of damage sustained. Most rotating
on-vehicle parts will be sufficiently closely balanced to normal
commercial tolerances during manufacture to behave satisfactorily.
Inevitably some will not and on-vehicle balancing is a way out.
Replacing a wheel stud is one possible way of unbalancing a hub
perfectly innocently.

The major disadvantage as previously mentioned is that the wheels/tyres
are then potentially location and orientation specific.

We don't know the full story behind the reported 'cure'. Let's not jump
to conclusions. It might just be the case of a less competant operative
of the off-vehicle balancing or a faulty balancing machine.

We had the wheels balanced on our Discovery by one of the 'quick' tyre
places and it stil shook at 70mph. When we had it in for some service work
the garage suggested a place has a clamp that rather than holding it on the
machine via the centre hole uses a clamp that fits on the wheel stud holes.
They said sometimes the centre hole is not dead centre. Anyway, had it done
and all signs of wobble have gone at any speed.
Richard


"hugh" <hugh@[127.0.0.1]> wrote in message
news:[email protected]...
> In message <[email protected]>, bones
> <[email protected]> writes
>>
>>"Bob Miller" <[email protected]> wrote in message
>>news:[email protected]...
>>> "Mother" <"@ {m} @"@101fc.net> wrote in message
>>> news:[email protected]...
>>>> On Mon, 18 Jul 2005 12:47:21 +0100, "bones"
>>>> <[email protected]> wrote:
>>>>
>>>> >How far out am i please?.
>>>>
>>>> I think this is the most incredible post I've ever seen on usenet.
>>>> No offence or anything, but don't you drive a truck for a living?
>>>>
>>>
>>> There are no stupid questions, only stupid answers! One of the best
>>> things
>>> about this NG (more than any other I look at) is that people can ask
>>> questions where the answers are obvious to others, and get a sensible
>>> response. If you don't know, and you don't ask, then you don't learn.
>>> --
>>> Bob Miller
>>> 1990 ex-RAF 110 3.5 V8 17KJ83
>>> 1967 3/4 ton Sankey 09ES17
>>>
>>>
>>
>>No offence taken,And yes i do.
>>The answer to my question is more than likely obvious to many on here.
>>I was asking as there *may*have been a reason that the weights varied from
>>wheel to wheel.
>>For example:
>>If you buy aftermarket coil springs,The front and rear poundage is
>>different
>>as is the left and right.
>>
>>
> Different situation all together. The weights are added to the individual
> wheels to compensate for imperfections in manufacture or arising due to
> everyday wear and tear. The weights are different simply because each
> wheel/tyre combination is slightly different. Without them the wheel would
> vibrate when rotating at high speed putting undue stress on bearings,
> suspension and steering, in extreme cases making the vehicle undriveable.
> This effect is most noticeable on the front wheels as the driver can feel
> the vibration through the steering.
>
> Equipment to balance the wheel/tyre combination has improved over the
> years but balancing has typically been done off the vehicle. Doing it in
> situ is I suspect largely motivated by the reduction in time taken by
> obviating the need to remove/replace each wheel. I've never seen one in
> action. There may be a slight improvement in the end result, I don't know,
> as there should be no or little imbalance in the actual hub/brake disc.
> Maybe someone else can be more definitive.
> --
> hugh
> Reply to address is valid at the time of posting

"Dougal" <DougalAThiskennel.free-online.co.uk> wrote in message
news:[email protected]...
> Mother wrote:
>
>> On Wed, 20 Jul 2005 17:13:55 +0000 (UTC), "TonyB"
>> <[email protected]> wrote:
>
> The advantage of balancing on the vehicle is that it is a way of enabling
> any imbalance of rotating parts other than the wheel/tyre to be treated
> without dismantling and balancing each individually. That imbalance may
> not be the result of damage sustained. Most rotating on-vehicle parts will
> be sufficiently closely balanced to normal commercial tolerances during
> manufacture to behave satisfactorily. Inevitably some will not and
> on-vehicle balancing is a way out. Replacing a wheel stud is one possible
> way of unbalancing a hub perfectly innocently.

I had a BMW 5 series (E39 model) and the only way to get a decent ride was
to have the wheels balanced on-car, after they had been done off-car. If you
fit a perfectly balanced wheel, then "trim" the weights to compensate for
any other rotational imbalance. This is becoming mnore frequent on modern
cars with lightweight ally suspensions, due to their being an insufficient
mass within the suspension itself to provide a damping effect for rotational
imbalance in hubs, driveshafts etc.

> The major disadvantage as previously mentioned is that the wheels/tyres
> are then potentially location and orientation specific.

Indeed.

> We don't know the full story behind the reported 'cure'. Let's not jump to
> conclusions. It might just be the case of a less competant operative of
> the off-vehicle balancing or a faulty balancing machine.

My BMW had bad vibes just after having had its rear wheels re-balanced,
another garage's balancer showed an exact imbalance of 61grams in the same
location relative to the added weights, on each wheel! On investigation, it
transpired that the balancer in garage no.1 had a bow in the mounting
shaft!!
Badger.

On or around Thu, 21 Jul 2005 08:14:32 +0000 (UTC), "Badger"
<[email protected]> enlightened us thusly:

>I had a BMW 5 series (E39 model) and the only way to get a decent ride was
>to have the wheels balanced on-car, after they had been done off-car. If you
>fit a perfectly balanced wheel, then "trim" the weights to compensate for
>any other rotational imbalance. This is becoming mnore frequent on modern
>cars with lightweight ally suspensions, due to their being an insufficient
>mass within the suspension itself to provide a damping effect for rotational
>imbalance in hubs, driveshafts etc.

course, if they were doing the job properly, they'd balance the hubs, shafts
etc. individually, then it wouldn't matter which bits are bolted on which
car.

It wouldn't surprise me in the least, however, if some bright spark hasn't
decided that it costs 20p less per car to resolve all the balancing into the
wheel.
--
Austin Shackles. www.ddol-las.net my opinions are just that
"'Tis a mad world, my masters" John Taylor (1580-1633) Western Voyage, 1

On Wed, 20 Jul 2005 23:41:35 +0100, Dougal
<DougalAThiskennel.free-online.co.uk> wrote:

>Balancing on the vehicle would not compensate for any damage to the
>steering or suspension.

Quite. "This technique successfully cured an out of true wobble on a
car I had which had been kerbed" - a car which has been 'kerbed' and
needs wheels balanced 'on the vehicle' to bring it true has been
'damaged'.

On Wed, 20 Jul 2005 17:13:55 +0000 (UTC), "TonyB"
<[email protected]> wrote:

>This technique successfully cured an out of true wobble on a car I had which
>had been kerbed. Normal balancing didn't do the job.

I'm somewhat concerned to believe that balancing a wheel 'on the
vehicle' should be seen as a viable option to compensate for damaged
steering or suspension.